Maybe omit the oil next time? I've always made it in a pan, with some herbs, etc. tossed on top. I don't really like the flavor. When I make it I put in in taco shells, cut across the slab, fajita style. I have also heard of people baking it, which would definitely cut down on any remaining liquid such that might cause "goo."

I eat a fair amount of tempeh, but I don't like plain soy tempeh at all. The tempeh I get is 3-grain, and is a blend of soy, rice, and millet. It has a much milder flavor. I usually eat tempeh raw, only letting it sit for a few hours in some teriyaki or other marinade. The best way I've found to enjoy it cooked is baking it with a marinade. Teriyaki is by far my favorite, as the tempeh really soaks it up well.

The traditional way is to fry them for ages on low heat, and then serve with a sauce made from chilli, garlic, sugar, kafir lime, and a bit of salt. I've got a pretty decent, "Not really Indonesian at all" cheat that takes barely much less time or effort.

Dice up your potato and your tempe into similar sized cubes. we're talking less than 2cm

You want to chuck all this in the oven to bake and dry out a bit, but because potato takes about a million years to cook, chuck only the potato in the microwave first for a headstart (don't put it in for more than a min at a time though)

Bake everything for a little while but take it all out before it starts to get golden

Chuck it all in a wok and stir-fry it with a little oil and kecap manis to your taste.

Serve as is or on a little rice, then throw on your favorite ass-bendingly hot sambal or indo chilli sauce

This has the added benefit of boosting your metabolism for a half-hour or so, haha